Bump actions/cache from 2.1.5 to 2.1.6 (#188)

Bumps [actions/cache](https://github.com/actions/cache) from 2.1.5 to 2.1.6.
- [Release notes](https://github.com/actions/cache/releases)
- [Commits](actions/cache@v2.1.5...v2.1.6)

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/ci.yml

@@ -26,7 +26,7 @@ jobs:
           node-version: ${{ matrix.node-version }}
 
       - name: Restore cached dependencies
-        uses: actions/cache@v2.1.5
+        uses: actions/cache@v2.1.6
         with:
           path: node_modules
           key: node-modules-${{ hashFiles('package.json') }}